1. Field of the Invention
This invention relates to the construction of a thermoplastic container produced by a blow molding process and to a method of handling a plurality of such containers. More particularly, this invention relates to the configuration of a removable moil portion of such a container that, before removal, facilitates the high speed handling of a multitude of like containers.
2. Description of the Prior Art
Many thermoplastic containers are produced, on a mass production basis, by blow molding on a blow molding machine of the xe2x80x9cwheelxe2x80x9d type. Such containers, each of which is produced with a removable excess portion known as a xe2x80x9cmoilxe2x80x9d above the rim that surrounds the opening into the container, must be handled at very high speeds, for example, in excess of 200 containers per minute, to permit the molding machine to operate at or near rated capacity. However, present handling techniques involve the handling of such containers on flat top vacuum conveyors, and the handling speeds of handling containers in this manner limit the rate at which containers can be handled to a production rate below that of the types of wheel blow molding machines in widespread use.
It is known that blown containers can be handled more rapidly by an air handling conveying system in which containers are suspended on spaced apart rails at locations well above the bottoms of such containers. However, in attempting to adapt such in an air handling container conveying system to the high speed handling of blown thermoplastic containers, it was found that it was difficult to maintain the containers with their longitudinal central axes parallel to each other, as required for proper handling.
The aforesaid and other problems associated with the high speed handling of blown thermoplastic containers are addressed by constructing each container, in its as molded condition, with a moil with outwardly projecting shoulders from which the container may be suspended during conveying along a portion of its travel path from a molding machine to a moil removal station, and by constructing each such moil with a lateral extent, along such travel path, such that contact between the moils of adjacent containers in contact with each other will maintain the longitudinal central axes of such containers parallel to each other.
Accordingly, it is an object of the present invention to provide a blown thermoplastic container with a removable moil that facilitates improved high speed handling of the containers after blowing and prior to the removal of the removable moil. It is also an object of the present invention to provide an improved method of handling a plurality of like blown thermoplastic containers in their as molded condition.
For a further understanding of the present invention and the objects thereof, attention is directed to the drawing and the following brief description thereof, to the detailed description of the preferred embodiment and to the appended claims.